Copiers, fax machines, digital senders, and scanners are often equipped with automatic document feeders (ADFs). Placing a multi-page original document in an ADF allows a user to issue a single common copy, fax, send, or scan, as the case may be, causing the particular device in question to sequentially process each page of the original document. So that the pages are processed in the correct order, the user is required to place the document in the ADF in either a face-up or face-down orientation.
Incorrectly placing a document in an ADF—that is placing the document face-up when it should be face-down or placing the document face-down when it should be face-up—results in (1) the device processing the pages in a reverse order and/or (2) the device processing the wrong side of each page. This can not only waste time and paper—it often results in user frustration.
Imagine incorrectly placing a twenty-five page single-sided document in the ADF of a fax machine. One side of each page contains text or other information, while the other side is blank. Once the sender enters a destination number and issues a fax command, the blank side of each page is processed and transmitted. The recipient receives a twenty-five page blank document, and the sender will often not recognize the mistake.